code: def output_types(self) -> Optional[Dict[str, NeuralType]]:
      output_types = super().output_types
      output_types.update(
          {
              "hidden_mask": NeuralType(("B", "T"), MaskType(), True),
          }
      )
      return output_types
  
imports: from dataclasses import dataclass
  from typing import Dict, Optional
  from nemo.collections.asr.modules.transformer.bridge_encoders import BridgeEncoder
  from nemo.collections.asr.modules.transformer.perceiver_encoders import PerceiverEncoder
  from nemo.collections.asr.modules.transformer.reduction_encoders import PoolingEncoder
  from nemo.collections.asr.modules.transformer.transformer import NeMoTransformerConfig, TransformerDecoderNM, TransformerEncoderNM
  from nemo.core.classes.common import typecheck
  from nemo.core.neural_types import MaskType, NeuralType
  from nemo.core.neural_types.elements import BoolType
label_desc: Use image node_id 4 for calling the TransformerBottleneckEncoderNM obj's underlying member method code with example usage: obj.output_types() and returns: output_types